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991.
An increased incidence in child abuse and neglect has resulted in a dramatic rise in the number of grandparents raising grandchildren and great-grandchildren. Grandchildren raised by grandparents often suffer from emotional and behavioral problems due to prior abuse, neglect, and abandonment. Grandparent caregivers experience increased health problems, psychological distress, and social isolation related to their roles as primary caregivers of children. Grandparents who become caregivers of grandchildren face increased financial responsibilities at a time in their lives, close to or at retirement, when income is dramatically decreased. 相似文献
992.
E Goodman BC Amick MO Rezendes AR Tarlov WH Rogers J Kagan 《Canadian Metallurgical Quarterly》1997,151(9):899-904
OBJECTIVE: To explore how gender and social class affect perceptions of health status among 16-year-old adolescents. DESIGN: Cross-sectional survey. SETTING: University psychology laboratory. PARTICIPANS: Fifty upper-middle-class and 48 working-class adolescents stratified by gender. MAIN OUTCOME MEASURES: The general health perceptions (GHP) scale of the Medical Outcomes Survey 36-Item Short Form Health Survey (SF-36). The other self-reported health status domains and 3 measures of different aspects of psychological well-being were included as covariates in analysis of variance models. RESULTS: Upper-middle-class females reported the lowest and upper-middle-class males the highest GHP (76.7 vs 88.4, P=.003). A multivariate regression model (adjusted R2=0.08) revealed significant gender (P=.03) differences in GHP, but not a social class effect, and an interaction effect between gender and class (P=.01). With addition of psychological well-being covariates (P<.001), gender remained significant (P=.04) and a significant portion of the interaction effect (P=.13) was explained. When the self-reported physical health status scales (P<.001) were added to the model (adjusted R2=0.51), gender remained significant (P=.03) and the interaction effect was partially explained (P=.07). CONCLUSIONS: Gender is a crucial factor in understanding the complex relationships between sociostructural inequalities and health differentials. These data suggest that psychological well-being and self-reported physical health status mediate the effects of gender and the gender and social class interaction in explaining variation in GHP. Contrary to the social class gradient hypothesis, upper-middle-class females reported the lowest GHP. These results suggest that the paradigms applicable to early childhood and adulthood may not be appropriate to understand the complex dynamics of adolescence. 相似文献
993.
994.
BC Furie JV Ratcliffe J Tward MJ Jorgensen LS Blaszkowsky D DiMichele B Furie 《Canadian Metallurgical Quarterly》1997,272(45):28258-28262
The propeptides of the vitamin K-dependent proteins contain a gamma-carboxylation recognition site that is required for gamma-glutamyl carboxylation. To determine whether the propeptide is sufficient to direct carboxylation, two mutant prothrombin species were expressed and characterized with regard to posttranslational gamma-carboxylation. A double point mutant, in which serine substituted for cysteines 17 and 22 disrupted a conserved loop formed by a disulfide bond, was fully carboxylated when expressed in Chinese hamster ovary cells. A propeptide/thrombin chimeric protein, constructed by deleting the Gla, aromatic amino acid stack, and kringle domains of prothrombin, has the signal peptide and propeptide juxtaposed to a glutamate-rich COOH-terminal region of prothrombin, residues 249-530. Of the 8 glutamic acid residues contained within the first 40 residues of the NH2 terminus adjacent to the propeptide, at least seven were fully carboxylated as demonstrated by direct gamma-carboxyglutamic acid analysis of the alkaline hydrolysate and by NH2-terminal sequence analysis. These results indicate that the gamma-carboxylation recognition site within the prothrombin propeptide in a prothrombin propeptide-thrombin chimeric protein is sufficient to direct gamma-carboxylase-catalyzed carboxylation of adjacent glutamic acid residues in a glutamate-rich region of thrombin that is not normally gamma-carboxylated. Furthermore, the disulfide loop in the Gla domain of prothrombin is not required for complete carboxylation. 相似文献
995.
JJ Dalluge BC Nelson JB Thomas MJ Welch LC Sander 《Canadian Metallurgical Quarterly》1997,11(16):1753-1756
The separation and detection of biologically active green tea catechins has been accomplished using capillary liquid chromatography/electrospray mass spectrometry (cLC/ESI-MS). Microscale determination (approximately 20 ng) of all six catechins in a green tea infusion, and the most extensively studied catechin, (-)epigallocatechin gallate (EGCG), in human plasma is demonstrated by cLC/ESI-MS with selected ion monitoring of protonated molecular ions. The overall quality of the analysis is shown to be dependent on the use of a capillary column with a deactivated, monomeric C18 stationary phase. The high chromatographic separation efficiency of this packed-capillary column, combined with the high sensitivity and selectivity afforded by the mass spectrometer as detector, provide a reliable approach to the analysis of picomolar quantities of these interesting compounds in complex matrices. 相似文献
996.
A newborn term male infant was found to have the stigmata of VACTERL syndrome, including cervical and thoracic hemivertebra, partial sacral agenesis, 13 pairs of ribs, high imperforate anus with rectovesical fistula, and tracheoesophageal fistula with proximal esophageal atresia. No open spinal dysraphism or skin dimpling was seen. Ultrasonography of the spinal cord was performed to screen for occult anomalies. The examination revealed a lipoma of the filum terminalis and a low-lying conus medullaris at the L3-L4 level with a large central cystic structure in the terminal cord, which was continuous with the central canal (Fig. 1). This was thought to most likely represent a dilated ventriculus terminalis, and the diagnosis was confirmed on a subsequent MR image (Fig. 2). Fluid in the cyst followed cerebrospinal fluid signal in all sequences. We observed no abnormal signal in the adjacent parenchyma or enhancement associated with the cystic mass. A cranial ultrasonogram did not reveal any intracranial anomalies. The patient demonstrated no neurologic deficits in the lower extremities. Bowel and urinary continence was not assessable in this infant. 相似文献
997.
BC Padberg J Woenckhaus G Hilger L Beccu W Jochum U Range H Kastendieck S Schr?der 《Canadian Metallurgical Quarterly》1996,20(7):815-822
Surgical material obtained from 100 patients with typical carcinoids (TC) and atypical carcinoids (AC) of the lung (including 100 primary, four residual tumors, and four lymph node or distant metastases) was investigated by conventional histology and scanning DNA cytophotometry. Of the 60 TC (96%), 58 exhibited euploid DNA histograms compared with only 20 (50%) of the 40 AC. The morphologic findings were related to the patients' survival (median observation period, 9 years). Statistical analyses disclosed the histologic type of disease (TC versus AC) and the DNA content of tumors (euploid versus aneuploid) to affect prognosis significantly (p < 0.001). Deaths resulting from tumor were exclusively observed among patients with atypical (eight of 40) or DNA aneuploid carcinoids (eight of 22). Six patients were alive with persistent tumor manifestations 3 to 20 years after initial diagnosis, four with DNA diploid primary carcinoids. The presence of lymph node metastases alone was not associated with poor prognosis as long as the primary tumor or the related metastases showed a diploid DNA content. DNA cytophotometry thus might be regarded as an adjunctive prognostic criterion in individual carcinoid cases. 相似文献
998.
We are in the midst of an epidemic of diabetes, and the prevalence appears to be especially marked within Delaware. To prevent tragic long-term complications of diabetes, and to minimize the enormous costs associated with treating them, an emphasis must be placed on the early diagnosis and aggressive management of diabetes. The changes in the classification, diagnosis and screening for diabetes should help to redirect the focus to one of preventive care. 相似文献
999.
MJ Polonio García JM Llamas-Elvira G Mi?o Fugarolas G Costán JL Jaramillo M Ure?a Lara MA Muros de Fuentes MD Martínez del Valle 《Canadian Metallurgical Quarterly》1996,13(7):331-335
The aim of this study is to evaluate gastric emptying change in patients with gastroesophageal reflux (GER). To this purpose, 36 patients with GER diagnosis and 18 control subjects have been studied. GER diagnosis was achieved by means of endoscopy, biopsy and 24 h continuous pH monitoring. Gastric emptying studies were performed on a two day basis, similar labelling meals were provided to patients and control subjects. Those consisted in a one-egg omelette, chicken (110 gr) and orange juice (200 ml). On first day liquid phase was labelled with 99mTc-diethylenetriamine pentaacetic acid (99mTc-DTPA), and on second day, the solid phase was labelled with 99mTc-sulfur colloid in the omelette (Labelling efficiency was 85.3 +/- 3.2%). The studies were carried out by imaging static anterior and posterior views every 20 minutes for a total of 180 minutes. Images were quantified obtaining solid and liquid gastric emptying curves. No statistical significative difference between patients and control subjects gastric emptying results were found. We can conclude that gastric emptying is not a main factor in the pathogenesis of gastroesophageal reflux. 相似文献
1000.
A theoretical proposal to double the pulse repetition frequency by alternating current modulation of two orthogonal high-order transverse modes of a vertical-cavity surface-emitting laser (VCSEL) is presented. Static and dynamic characteristics of weakly index-guided VCSELs in a multitransverse mode regime are analyzed. An efficient model that takes into account all the transverse modes supported by the waveguide is developed. Mode partition noise in a current modulated VCSEL is studied, taking into account the azimuthal degree of freedom. Different transverse modes can be excited with a probability that is numerically calculated. For high injection currents, modes that are not favored in the steady state can be excited with higher probability. The excitation probability is similar for azimuthally orthogonal modes. This symmetry can be broken by selecting a particular high-order transverse mode by using azimuthal-dependent current profiling. This selection can be achieved over current ranges as wide as ten times the threshold current. Current modulation of this transverse mode is then analyzed. Alternate current modulation of two orthogonal high-order transverse modes is also studied. Alternating modulation of these modes can double the pulse repetition frequency obtained by modulating just one high-order transverse mode, without increasing injected current density levels. This current-induced spatial switching leads to high-frequency beam steering in the laser azimuthal direction 相似文献